Vintage MTB to gravel/adventure bike

careca78

Hello all

I've have never owned a gravel bike, as they are not very popular in Portugal, but I got curious and since I live in an area with a lot of fire roads I've decided to give it a go, but given the current bike prices I ended up buying a 1993 GT Timberline for a project, to convert it to a gravel/adventure bike.



In stock condition it weighed around 12,5kg and the frame alone around 2.65kg.
The bike showed signs of been laying around without getting used much and apart from the typical stuff that comes with age it seemed to be in a really good shape.



After a complete disassembly and cleaning I've found the hubs, rims, deraileurs, BB, etc. where all free of corrosion, play and were all usable again and so reassembly was next.



And now comes the tricky part... compatibility issues!
I would like it to have:
- Keep the current 3x7 transmission (cost)
- Keep the cantilever brakes (cost)
- Put dropbars

Unfortunately the stem is 25,4mm, so it's hard to find a decent dropbar, I've only found a 3x7 brake/shifter levers for dropbars from Microshift and I'm not sure if they are compatible with cantilever brakes.

I would like to have your opinion about the following:
- Should I keep the MTB 3x7 shifters and just buy brake levers?
- Should I change the stock stem and put an adapter to fit normal stems for 31,8mm?
- Are Microshift brake/shifter levers any good?

Sorry for the length of this post and tell me what you think

davidof

I converted a flat bar bike to drop bars. The Microshifts (which I have) are okay levers and will work with mini V brakes like these:-

https://www.chainreactioncycles.com/se/en/tektro-926al-mini-v-brake/rp-prod34580

For the front brake I had to put a brake power modulator that prevents the front brake locking. You may decided you don't need this but the pull on the microshift is different from the flat bar brakes.

I would go for microshifts and get rid of the canti brakes and replace with something similar to above.

As ever, working with obsolete kit is a bit of a nightmare.

careca78

Thanks for the inputs.

For the sake of trying to keep married, I'm now considering in keep costs to the minimum... so, I will keep the MTB shifters and just buy a drop bar and a set of brake levers (30€ instead of 90€).
I will also keep the cantilevers and if I can get a "gravelish" drop bar with 25,4mm I will also keep the original stem.

I have to agree with you regarding the difficulties with working with obsolete kit, but on the other hand it's still better than spending my time watching TV

It will look like a frankenbike, but I'm already planing on some long trips with it...

singleton

I watched a GCN video today that might give you some inspiration. I hope I'm not breaking any rules by putting a link in.

Watch this from about 19 minutes in: https://youtu.be/EM4Lblb1qN4

careca78

Nice video!
The old GT frames, especially steel ones, have a very distinctive look. That was the main reason for buying this bike.
I also have a sweet spot for steel bikes, with the GT being the third one.

One of the reasons I'm trying to save money right now is to later upgrade the full transmission to a 1x9 or 1x10 if riding the bike makes me smile.

I already have a One-One 456 Evo II with Shimano SLX 1x10 with a Sunrace 42T cassette and I love it!

davidof

singleton said:

I watched a GCN video today that might give you some inspiration. I hope I'm not breaking any rules by putting a link in.

Watch this from about 19 minutes in: https://youtu.be/EM4Lblb1qN4

GT cool !

careca78

oxoman said:

Why not ditch the drop bars and use it with bar ends or similar. Won't look as frankenbike.

I already have a proper MTB (or three) and a road bike... another steel classic...

I wanted something completely different from what I'm used to and with the gravel/adventure/mile crunching vibe... in reality there is no logical reasoning behind all this... maybe I'm just bored with all this COVID restrictions everywhere

mully79

i have a 95 Giant peloton which has the 25.4mm drop bars/quill stem and Rx100 7 speed brakes/gear shifters.

Unfortunately I have the same plan to do exactly the same to an Orange P7

Planet X do sell a set of drop bars at 25.4mm and road 25.4 stems (ie -17.0 Deg) (Nitto).
The shifters are probably the difficult bit to source.

careca78

Microshift has options for 2x7 and 3x7 speed transmissions , both deraileurs and brake/shifter levers.

I'm still looking for drop bars in 25,4mm, but the things I've found so far are usually to narrow and road focused, so I've started to look in the travel/expedition/niche community.

PMark

I am currently building up a 90s steel road bike and am just going to get some of the stem adapters, like this. https://www.wiggle.co.uk/brand-x-quill-adaptor-alloy?lang=en&curr=GBP&dest=1&sku=100277811&utm_source=google&utm_term=&utm_campaign=&utm_medium=base&gclid=CjwKCAjwm7mEBhBsEiwA_of-TO2cfjd0LPgG3rNvGrKM4cy8EcrzIgMhgbj4gOgOb2mJpJJ2BgbAAhoCbNsQAvD_BwE&gclsrc=aw.ds

Then I will be able to fit a modern stem and drop bars. Was also toying with the idea of getting a suspension stem, but will just use the gel padding under the bar tape initially and see how that goes.

careca78

Quick update... I've got the approval from Mrs. Careca78 and bought a bunch of new parts!

So, I'm getting a quill adapter to fit a proper 31.8mm stem and gravel drop bar, a new headset and 3x7 Microshift brake/shifter levers... life is good

careca78

The bike is finally done!
I've managed to keep the weight at 12,5kg and cost under 300€.

Frame/Fork: GT Timberline 1993
Crankset: Sugino (something from 1997)
Brake levers/shifters: 3x7 Microshift R473 (NEW)
Brakes: Shimano cantilever
Tyres: Schwalbe CX COMP Active cross tyre 26x2,0 (NEW)
Stem: Brand-X Road Stem 90mm (NEW)
Headset: Brand-X (NEW)
Quill Adaptor: Brand-X (NEW)
Handlebar: Ritchey Comp Venturemax 44cm
Seatpost: Onoff
Front Derailleur: Shimano Exage
Rear Derailleur: Shimano Exage
Wheels: Shimano Exage hubs with Sun rims

careca78

So, I went for a ride last weekend and all went well except for a mid-trail adjustment on the brakes, because the levers had to much slack.

The bike has some very distinctive characteristics, so I will try to summarize its pros and cons:
- Microshift brake levers/shifters work just fine and definitely provide a cheaper solution to revive those older bikes
- With 12,5kg it's not a XC lightweight, but coming from a On One 456 with nearly 14kg it's light enough for the intended purpose
- The 7x3 gears, with the biggest rear cog with only 30T, are not super climbing-friendly for my current shape... but the fault is on me
- The cantilever brake pads are still bedding in, but the braking performance is not something to write home about...
- The bike picks up speed REALLY fast... I don't know if the merit goes to the tires or the serviced hubs
- The ride is bumpy but the steel frame and wide, flexy bar help keep it fairly comfortable
- During steep climbs the front wheel is very wobbly... I have an extra 60mm stem and I'm thinking about trying to see if it can make it more stable
- My (cheap and used) seat is not very balls-friendly and I don't need a redneck vasectomy, so I'm thinking about buying a new one.
- The wheels are smooth and running straight, but with the tolerances allowed by the cantilevers it means you have to check them regularly

In conclusion, this is a really nice way to revive that old bike you have laying around and it doesn't have to be expensive... but beware, it's very easy to fall into the trap of wanting to start buying new stuff and upgrading... right until to get into compatibility issues